Such coupling devices or fluid connectors are already known in the art. For example, if a connecting conduit, especially a corrugated pipe or the like is to be reversibly connected with its union onto a connecting element, corresponding reversible connectors are used in order to connect the connecting union of the pipe to a corresponding connecting portion.
A connector for pipes is known, for example, from EP 0 756 125 A1, wherein spring arms with stop shoulders which extend in the actual direction of the connector grip behind a corresponding holding ring on the connecting element and thereby hold the connecting element. This type of connector provides difficulties when the connecting element is to be separated from the connector. An additional ring can be provided for the opening of the connector, whereby this ring when forced in axial direction into the connector forces the arms radially outwardly to free the holding ring of the connecting portion. However, an undesired axial movement of the additional ring for the releasing or opening of the connector can lead to an unintended release of the connecting element.
A corresponding, much more complicated coupling connector is also known from DE 43 00 037 C1, whereby in that connector V-shaped spring arms have holding portions therebetween which are moved in guides radially outward by a radial compression of both V-shaped spring portions in order to accept a grip behind portion of a connecting element. After release of the V-shaped spring portions, the holding portions once again move radially inward and grip behind the grip behind section of the connecting element. This connector also depends solely on the flexibility of the locking element and at low temperatures when the plastic from the which the locking element is made becomes hard, the spring elements can break or it becomes relatively difficult to operate the spring elements of the lock element.